Modifying Photo and Photo Collection Properties

Photo data can be viewed and modified in the photo collection property sheet and photo list. Information displayed in the property sheet refers to the collection that is currently selected in the collections list, while information in the photo list is specific to each photo.

Information about the photo collections and photos (e.g., coordinate system, sensor width, focal length, photo position information) is generally read from a loaded Excel or XML file that includes this information. These parameters can then be adjusted in the collection property sheet and photo list.

Properties can be edited even after aerotriangulation, up until the reconstruction step starts. When rebuilding, if any change was made to photo/collection properties, the build is restarted from pre-aerotriangulation.

To display and modify photo collection properties:

1. In the Project Tree, select the Photos group.

2. In the collection property sheet , modify the property values as required. See "Collection Property Sheet" in this chapter for more information.

To display and modify photo properties:

1. In the Project Tree, select the Photos group.

2. In the Photos list, select the required photos, and modify their properties as required. See "Photos List" in this chapter for information.

Note: You can also search the list for the required photos. See "Selecting Items Using the Item List" in the "Basic Concepts" chapter for information.

Collection Property Sheet

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Note: If one or more of the camera properties that are used to set the focal length (These properties vary depending on the Focal Length Normalization property setting set in the Collection property sheet) is missing, an orange question mark is displayed next to the property.

Property	Description
Collection
Name	Name of the collection in the Photos list.
Coordinate System	Coordinate system of the collection. Click Select to set a different coordinate system. See "Coordinate System" in the "Basic Concepts" chapter for more information.
Orientation Method	Select which system to use to set orientation: OPK (Omega, Phi, Kappa) or YPR (Yaw, Pitch, and Roll). This selection determines which fields are displayed in the Advanced Position section of the property sheet.
Altitude Type	When both relative and absolute altitude data were provided, this property sets the altitude method to be used by the collection. Select Relative to Terrain to place the collection at a specified altitude above the ground. Select Absolute to place the collection at a specified altitude above the terrain database vertical datum base ellipsoid.
Relative Altitude	If "Relative" was selected as the Altitude Type, this defines the altitude above the ground.
Camera
Focal Length Normalization	Camera properties used to set the focal length. Select one of the following options: § Focal length and sensor width § Focal length and pixel size § Focal length 35
Sensor Width	Size of the camera sensor in millimeters.
Pixel Size	Size of a physical pixel on the camera sensor in millimeters.
Focal Length	Focal length in millimeters.
Focal Length 35	Equivalent focal length in millimeters for a 35 mm film camera.
Principal Point Reference	Origin and units of the principal point. Select one of the following: § Top left in pixels – Positive x-direction is to the right and positive y-direction is downwards. § Top left in mm – Positive x-direction is to the right and positive y-direction is downwards. § Center in pixels – Positive x-direction is to the right and positive y-direction is upwards. § Center in mm – Positive x-direction is to the right and positive y-direction is upwards.
Principal Point X	Principal point X value in pixels or mm according to principal point reference.
Principal Point Y	Principal point Y value in pixels or mm according to principal point reference.
Width	Width of photo in pixels.
Height	Height of photo in pixels.
Gamma	Brightness of the photo’s colors. The default value of 1 leaves the color unchanged. Values >1 brighten the colors, while values <1 darken them.
Effective Range	Maximum distance from the camera position for which photo information is considered valid for the aerotriangulation.
Calculated Effective Range	Whenever the Effective Range parameter value is not provided, PhotoMesh calculates the maximum distance from the camera for which photo information is considered valid for the aerotriangulation, and then displays and uses this value.
Crop Area	Percentage of the photo to use in the project. Blurry or obstructed areas on the edges of a photo will be cropped based on this property value.
Use in Textured Model	Select the check box to include this collection in the textured model.
Use in Orthophoto	Select the check box to include this collection in the orthophoto.
Use as Reference Only	Select the check box to include this collection only in the reference project. See "Adding a Reference Project to Use in Aerotriangulation" in the "Control Points" chapter for information.
Use in Point Cloud	Select the check box to include this collection in the point cloud output.
Bands – Multispectral Note: The band information is retrieved from the collection information in the photo list Excel or XML, the collectionProperties XML, or from the first photo in the collection. See "Loading a Photo List File" and "Loading Photo Files from Disk" in the "Photo Management" chapter. You can manually set the value for each band in the property sheet.
Multispectral Bands	Multispectral bands in the collection’s photos. These bands can be used in texturing the 3D model and in generating the orthophoto. See "Setting Advanced Reconstruction Parameters" in the "Building" chapter.
1	Select the first band.
2	Select the second band.
3	Select the third band.
Camera Distortion (Optional) Radial and tangential distortion calculated using the Brown-Conrady model. See here for more information.
K1	Defines the 1^st radial distortion coefficient.
K2	Defines the 2^nd radial distortion coefficient.
K3	Defines the 3^rd radial distortion coefficient.
P1	Defines the 1^st tangential distortion coefficient.
P2	Defines the 2^nd tangential distortion coefficient.
Advanced Position (Either OPK or YPR offset and flip values will be displayed, depending on your selection above for Orientation Method)
Altitude Offset	Offset from the current altitude value.
Omega Offset	Offset in degrees along the Omega axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Phi Offset	Offset in degrees along the Phi axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Kappa Offset	Offset in degrees along the Kappa axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Yaw Offset	Offset in degrees along the Yaw axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Pitch Offset	Offset in degrees along the Pitch axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Roll Offset	Offset in degrees along the Roll axis from the photo's provided angle. Applied before any additional rotation and prior to calculating position/orientation, this property helps correct orientation discrepancies between a camera and the plane on which it is mounted.
Flip Omega	Flips the Omega axis.
Flip Phi	Flips the Phi axis.
Flip Kappa	Flips the Kappa axis.
Rotate Yaw	Additional rotation along the Yaw axis in degrees, that is performed in YPR order after the photos' OPK or YPR orientation and offsets were applied
Rotate Pitch	Additional rotation along the Pitch axis in degrees, that is performed in YPR order after the photos' OPK or YPR orientation and offsets were applied
Rotate Roll	Additional rotation along the Roll axis in degrees, that is performed in YPR order after the photos' OPK or YPR orientation and offsets were applied
Accuracy Note: The "Use build settings" option for the properties below sets the accuracy value based on the build settings for the project. For more information on this and other accuracy parameter options, see "Setting Advanced Aerotriangulation Parameters" in the "Building" chapter for information.
Ignore Orientation	Ignore the orientation value.
Horizontal Accuracy Factor	Weight to assign to the photos’ provided XY coordinates in determining the calculated XY values. This ranges from Very High - External AT (Factor = 100) to Unreliable (Factor = 0).
Vertical Accuracy Factor	Weight to assign to the photos’ provided altitude in determining the calculated altitude value. This ranges from Very High – External AT (Factor = 100) to Unreliable (Factor = 0).
Focal Length Accuracy	A percentage that indicates the allowable deviation from the provided focal length value when calculating the AT. This represents the accuracy of the provided focal length. This ranges from Use Input Value to Unreliable.
Principal Point Accuracy	A percentage that indicates the allowable deviation from the provided principal point when calculating the AT. This represents the accuracy of the provided principal point. This ranges from Use Input Value to Unreliable.
Radial Accuracy	Radial accuracy. It is generally recommended to select the "Standard" option. If your data was captured with a professional camera that automatically applied a radial distortion correction (i.e., the original distortion value is extremely accurate), select "Use input value".
Tangential Accuracy	Tangential accuracy. It is generally recommended to select the "Standard" option. If your data was captured with a professional camera that automatically applied a tangential distortion correction (i.e., the original distortion value is extremely accurate), select "Use input value".
Calculate Camera Parameters	Method of calculating the camera’s intrinsic parameters. § Use Build Settings – Use the method selected in the "Calculate Camera Parameters" AT build parameter. § Entire collection – Calculate the AT so that the camera intrinsic properties are the same for all photos in the collection. § Per photo – Calculate the camera intrinsics individually for each photo in the collection. Note: Parameters should be calculated per photo when not all of a collection’s photos were taken by the same physical camera with identical focal length and principal point.

Collections List

In the Collections list, you can view collection properties. These properties can be edited in the Collection Property Sheet. See "About the Item List" in the "Using the Project Tree and Item List" chapter for information on working with the Collections list.

Collections List

To open the Collections list:

§ In the Project Tree, select the Photos group. The Photos list is displayed showing two tabs. Click the Collections tab. The Collections list lists all the collections in the project, with the following information/options:

Property	Description
Selection	Select the collection on which to perform an action.
Visible	Select the check box to show the collection in the 3D Window.
Exclude	Select the check box to exclude the collection from the project.
Name	Name of the photo collection.
Number of Photos	Number of photos in the collection.
Sensor Width	Size of the camera sensor in millimeters.
Pixel Size	Size of a physical pixel on the camera sensor in millimeters.
Focal Length	Focal length in millimeters.
Focal Length 35	Equivalent focal length in millimeters for a 35 mm film camera.
Width	Width of photos in pixels.
Height	Height of photos in pixels.
Principal Point X	Principal point X value in pixels or mm according to principal point reference.
Principal Point Y	Principal point Y value in pixels or mm according to principal point reference.
Altitude Offset	Offset from the current altitude value.
Omega Offset	Offset along the Omega axis in degrees.
Phi Offset	Offset along the Phi axis in degrees.
Kappa Offset	Offset along the Kappa axis in degrees.
Horizontal Accuracy	Accuracy of the photo’s provided X and Y coordinates.
Vertical Accuracy	Accuracy of the photo’s provided altitude.
Focal Length Accuracy	Accuracy of the camera’s inputted focal length.

Photos List

In the Photos list, you can view and set photo properties, as well as set photo visibility and inclusion in the project. When calculated camera positions are displayed, you can also view calculated property information for a selected photo. See "About the Item List" in the "Using the Project Tree and Item List" chapter for information on working with the Photos list.

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Photo List

To open the Photos list:

§ In the Project Tree, select the Photos group. The Photos list is displayed showing two tabs. Click the Photos list to view a list of all the photo files in the project, with the following information/options:

Property	Description
Selection	Select the photos on which to perform an action, e.g., create tie point, show/hide camera symbol, exclude, delete.
Collection	Name of the photo collection (Read-only).
Name	Name of the photo.
Visible	Select the check box to show the photo in the 3D Window.
Exclude	Select the check box to exclude the photo from the project. This option is not available in Review mode.
Project Original	Select the check box to project the photo on the terrain in its provided camera position. A photo can be projected on the terrain to see if it fits the terrain imagery or to better understand the position of the photo. Only photos that have positioning (XY coordinates and altitude) and orientation (Omega, Phi, and Kappa) information can be projected. Note: Projecting multiple photos simultaneously can take several minutes.
X	East-west coordinate of the camera. (Required)
Y	North-south coordinate of the camera. (Required)
Altitude	Altitude of the camera in meters. (Required)
Omega	Omega Euler angle in degrees.
Phi	Phi Euler angle in degrees.
Kappa	Kappa Euler angle in degrees.
Yaw	Direction angle of the camera along the vertical axis relative to north.
Pitch	Tilt angle of the camera along its lateral axis relative to the horizon.
Roll	Roll angle of the camera along its longitudinal (front-to-back) axis.
Path	Full path of the photo.
K1	Defines the 1^st radial distortion coefficient.
K2	Defines the 2^nd radial distortion coefficient.
K3	Defines the 3^rd radial distortion coefficient.
P1	Defines the 1^st tangential distortion coefficient.
P2	Defines the 2^nd tangential distortion coefficient.
Calculated Cameral Position Information (Additional columns) Note: If you want to view calculated information for a selected photo, click the Calculated button on the Tile tab.
Project Calculated	Select the check box to project the photo on the terrain in its calculated camera position.
Median Error	Median of the triangulation errors of all the features in the photo. The triangulation error is the distance, in pixels, for each of the features in the photo, between the automatically identified feature and its projected triangulation position.
X Calculated	Calculated east-west coordinate of the camera.
Y Calculated	Calculated north-south coordinate of the camera.
Altitude Calculated	Calculated altitude of the camera in meters.
Omega Calculated	Calculated Omega Euler angle in degrees.
Phi Calculated	Calculated Phi Euler angle in degrees.
Kappa Calculated	Calculated Kappa Euler angle in degrees.
K1 Calculated	Calculated 1^st radial distortion coefficient.
K2 Calculated	Calculated 2^nd radial distortion coefficient.
K3 Calculated	Calculated 3^rd radial distortion coefficient.
P1 Calculated	Calculated 1^st tangential distortion coefficient.
P2 Calculated	Calculated 2^nd tangential distortion coefficient.